1. Field of the Invention
Aspects of the present invention relate to a fuel cell stack having stacked unit cells in which an electricity generation reaction takes place, and more particularly, to a fuel cell stack having an improved sealing structure of a cooling plate and a fuel cell having the fuel cell stack.
2. Description of the Related Art
A fuel cell is an electric generator that changes chemical energy of a fuel into electrical energy through a chemical reaction, and the fuel cell can continuously generate electricity as long as the fuel is supplied. That is, when air that includes oxygen is supplied to a cathode, and hydrogen gas which is a fuel is supplied to an anode, electricity is generated by a reverse reaction of water electrolysis through an electrolyte membrane. However, generally, the electricity generated by a unit cell does not have a high voltage to be used. Therefore, electricity is generated by a stack in which multiple unit cells are connected in series.
In the above electrochemical reaction, not only electricity but also heat is generated. Thus, in order for the fuel cell to be smoothly operated, the heat must be removed by circulating a coolant through the fuel cell stack. However, if the coolant leaks, there is a serious problem in cooling the fuel cell stack. Therefore, the sealing of coolant is important for maintaining the performance of the fuel cell.
Therefore, in order to have a smooth operation of a stack, there is a need to develop a structure of cooling plate that can strictly prevent coolant leakage.